2010年10月26日上午9时，随着两列国产“和谐号”CRH380A新一代高速动车组从上海虹桥站、杭州站同时疾驶而出，沪杭高速铁路通车运营．这是我国高速铁路引领世界高速铁路发展潮流的又一重要标志．

为了适应火车提速，沪杭线上原有的短轨都需要连接为超长轨．工人常用2Al+Fe₂O₃Al₂O₃+2Fe这一反应原理来焊接钢轨．则反应物中具还原性的物质是 ____

用“who”或“that”填空
(1) The man____  is talking with my mother is my father .
(2) That book is the one____  I bought yesterday .
(3) He is one of the workers ____  been saved in that accident .
(4) They talked of the things and persons ____  they remembered in the factory .
(5) All____  can be done must be done .